FLOOD10389 ‎(2)‎

• Designation Number: 577
• County: Conejos
• Community: Manassa
• Stream Name: Conejos River
• Title: Floodplain Information Report - Manassa Colorado
• Date: 8/1/2004
• Prepared For: Manassa and CWCB
• Prepared By: Love and Associates
• Floodplain - Doc Type: Floodplain Report/Masterplan

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

STUDY AREA DESCRIPTION

Community Description

The Town of Manassa is located within Conejos County, Colorado, in southern Colorado.
Please refer to the Vicinity Map, Figure 1. Manassa has a population of approximately
1000 people. No streams are found within the Town. The Town is located within a
semi-arid climate and precipitation averages about 12 inches per year at the USGS
Stream Gage 08248500 located a few miles east of Manassa. Generally, most
precipitation falls as rain during the summer. The mean annual temperature is
approximately 420 F; the average temperature in January is approximately 190 F and the
average temperature in August is approximately 620 F.

Watershed Description

Manassa is located at an elevation of approximately 7680 feet in the San Luis Valley on
the plains just north of the North Branch Conejos River and about 10 miles west of the
Rio Grande River within the Rio Grande Basin. The Conejos River originates at the
continental divide in the San Juan Mountains; much of its basin is located within public
lands.

Floodine Problems and Floodine History

Flooding in Manassa was reported in the fall of 1911. Photographs of the flood show
flooding less than one-foot deep within the Town.

Previous Studies

There are no hydrologic or hydraulic studies of the area identified as a Zone A floodplain
on the Manassa FIRM (FEMA, 1986); please refer to Figure 2.

Community Response to the CWCB Desienation and Approval Process

A letter from the CWCB was transmitted to the Town of Manassa regarding the Board's
proposed action for designation and approval of Manassa floodplain information. The
town was receptive to the Board's proposed designation action and sent an official letter
requesting that the CWCB designate and approve the floodplain information currently
available to the community. A copy of the request letter is included in the Appendix of
this report. In addition, the community was contacted during the study process to obtain
data and general information.

4